Under the terms of the deal, Iran agreed to pause some of its nuclear activity, as well as allow intrusive visits by international inspectors. The U.S. and its partners agreed to drop some of its sanctions, which amount to about $6 billion in relief.

The BBC reports that under the deal Iran also promised not to "commission or fuel the Arak reactor" during the six-month period. The BBC adds:

"The Arak heavy water production plant is designed to supply a research reactor under construction nearby.

"The Arak reactor is significant because if completed, it could open the way for the reprocessing of plutonium — a potential step towards a nuclear weapon."

The U.S. insists Iran is racing to develop a nuclear weapon, while Iran says its nuclear program is for peaceful purposes.

The team from the International Atomic Energy Agency should complete their one-day inspection today, Reuters reports. They will be back on a plane to Vienna tonight.

Meanwhile, two bits of news have bubbled up about the deal:

-- According to the AP, Iran's President Hassan Rouhani said the interim deal with world powers had "already boosted the country's economy."

-- As we reported, President Obama also defended the deal with Iran on Saturday during a conversation at a yearly forum for American and Israeli leaders. Obama said the U.S. would be OK if Iran retained some enrichment capabilities.